Width is not the problem with the 295s. Height is.
The rolling diameter of the 275-60-15 tires is 28". The 295/50-15s are 1.3" shorter at 26.7" dia. With a Mangusta, you need as much rear tire height as you can get so the wheel well is filled nicely, and the ZF isn't dragging on the ground (or the skid-pates, if you have).
The perfect tire would be the no-longer available 305/50-15 Euro T/As.
Mark
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